I'm not sure what an alternative would be but I just used an INNER JOIN and it did the trick.
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AlxVallejoJan 10 '12 at 20:18

I was gonna suggest deleting from within a script by getting post objects with WP_Query and then iterating through them...mostly because handtyped sql is easy (for me at least) to botch. Kudos if you got it though.
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mor7iferJan 10 '12 at 20:22